Little acrobat, the Tufted Titmouse.
Bird Watcher’s Digest: “Regulars at backyard bird feeders, where they prefer sunflower seeds, peanuts, and suet, Tufted Titmice are both active and vocal. In winter, they may join mixed feeding flocks of chickadees, nuthatches, and others.”
Peter, peter, peter, peter! is the clear, whistled song of the Tufted Titmouse. Also utters a harsh chickadee-like scold and a variety of short, sweet, whistled calls.